For many decades, the supposed nuclear balance of power has been based on deterrence--the concept that no-one can prevent a nuclear strike, so no-one should attempt one. In the classic irradiated chess-game thinking brought about by the bomb, the analysis goes as follows:
In game theory terms, the nuclear balance is a prisoner's dilemma; each side is tempted to play the betrayal card, but refrains from doing so because of the shadow of the future.
I feel almost helpless before the task of explaining why I believe there is no such thing as nuclear strategy. It would require a treatise rather than an essay; and even then it would be like explaining to a paranoid schizophrenic that the McKinsey Corporation doesn't really run the world.
First principle: even conventional war involves much less "strategy" than most people think. In fact, the idea of "strategy" can be seen as a convenient self-deception, promoting self-confidence and ultimate survival in the face of utter chaos. In War and Peace, Tolstoy brilliantly deconstructed a battle, illustrating that the generals had no idea of what was actually happening in the field, communications were almost nonexistent and largely inaccurate or arrived too late to be of any use; and the results had more to do with luck or chance than anything else. Anyone who has studied World War II closely knows this to be true. The war was chock-full of tactics, most of them ill-begotten, but showed very little strategy; unless "be able to pour more men and machines in than your adversary" is a strategy. Of course, it isn't; its an accident of birth.
The Second World War was won entirely because the United States could ultimately afford to lose more men, transports and weapons than the weakened Germans. Studies like Ryan's well-known works on Normandy and Operation Market Garden reveal that war is not really predictable, because everything always goes wrong. Pilots panic and paratroopers are dropped far from the drop points. Or, when they are dropped on target, the destination turns out to be a marsh rather than a field, and they drown. The radios don't work. The artillery shells the wrong place (or our own troops). The supplies are dropped in a zone held by the enemy. Similarly, John Keegan's analysis of the battle of Midway reveals the supreme role of chance. One moment, we have taken severe blows, and the battle is almost lost; the next, our planes happen to find the Japanese carrier in the middle of the sea, and the battle is won.
Secondly, nuclear "strategy" is entirely self-referential, and therefore cancels itself out of the picture entirely. Imagine if in a chess game, each player had the ability to create a new piece which was not governed by any of the rules already in place governing the movement of pieces on the board; both players creating such pieces adds nothing to the existing strategy of the game and confers no advantage. In the end, I do not need a nuclear weapon because it will help me play the game better; I need one because my opponent has one too. This creates a completely unstable situation, of course, as we each now seek to create a new piece that will trump the other's "super-piece".
Third, it follows from this that nuclear weapons, as the history of the last fifty years clearly shows, have not deterred conventional wars:
However, one can speculate that other conditions than the bomb would have prevented another World War in the last fifty years. Russia had twice proved itself invulnerable to conventional attacks, once by Napoleon, once by Hitler; it is too big and cold, and there are too many people, to conquer it with troops and tanks. Similarly, the United States is too big, and geographically remote, to conquer; during World War II, no serious plan of invading the U.S. was ever entertained either by the Germans or the Japanese. Perhaps another European war might have occurred, this time between the U.S. and the Russians; but once Stalin had rolled up Eastern Europe as a buffer against us, which we allowed him to do based on political concessions after the war, it is hard to say that, in the absence of the bomb, he would have been of limitless geographical ambition in the face of conventional forces.
Because the bomb exists, we have been forced to incorporate it in our thinking; but, like a man living with a bullet embedded near the heart, it cannot be said that we live better because of it. It is an unstable bullet, constantly shifting; thinking about it all the time makes the nerves scream; it is a burden impossible to bear.